Reduced Efficacy of Coronary Artery Bypass Grafting in Women

During a six-year period (August, 1978-May, 1985), 1,089 patients underwent isolated, primary, elective coronary artery bypass grafting (CABG) at St. Margaret's Hospital, Montgomery, Alabama. The group consisted of 833 (76.5%) men and 256 (23.5%) women. The women were older (mean age, 59.7 years vs. 55.4 years for men) ( p = .0001), had more severe preoperative angina pectoris (mean New York Heart Association functional class 3.3 vs. 3.1) ( p = .008), and had higher incidences of adultonset diabetes mellitus (24% vs. 13.5%) ( p = .0001) and preoperative congestive heart failure (8.2% vs. 3.7%) ( p = .003). The overall mortality was 1.9% (21/1,089 patients); there were 10 deaths among the men (1.2%) and 11 deaths among the women (4.3%) ( p = .001). Univariate and multivariate analysis of preoperative variables indicated that the female gender factor ( p = .002), age of 70 years or older at operation ( p < .001), preoperative left ventricular dysfunction ( p = .026), preoperative congestive heart failure ( p < .001), renal insufficiency ( p = .036), peripheral occlusive disease ( p = .002), extracranial occlusive disease ( p = .001), and chronic obstructive pulmonary disease ( p = .017) all had significant influences on hospital mortality. Perioperative myocardial infarction ( p = .017), low cardiac output ( p < .001), and respiratory failure ( p < .001) significantly influenced outcome as well. Long-term (five-year) overall survival (90%) indicates a significantly superior overall survival among men ( p = .0008). Event-free survival (absence of cardiac death, myocardial infarction, or recurrent angina pectoris) was significantly superior among the men ( p = .03) as well. These data generally agree with other studies that indicate the early, late overall, and event-free survival following CABG is superior in men.